1. Field of the Invention
The present invention relates to an encoder, an optical module, and a servo system.
2. Description of the Related Art
As an optical encoder, a reflective encoder has been known as, for example, in JP, A, 2003-130689. In the reflective encoder, a point light source is used. Irradiation light from the light source is reflected by a reflection slit. The reflection light is received by a light receiving element. Then, the position of an object to be detected is detected from the light reception signal.